Self-aligning wheel structure

ABSTRACT

Power operated legs pivot curved feed radially outward of a wheel for fixing the rotary wheel position as upon uneven terrain or in the presence of exterior forces tending to rotate the wheel. When retracted the feet circumferentially fit the wheel for ready rolling of the wheel to another location.

United States Patent 11 1 Gorzell Nov. 20, 1973 [54] SELF'ALIGNING WHEELSTRUCTURE FOREIGN PATENTS OR APPLICATIONS Inventor: Keith Gomll, BOX502, 246,424 8 1963 Australia 239 212 Lake City, Calif. 96115 422,841 121925 Germany 301 46 900,056 9 1944 France 301/46 [22] May 1972 1,050,8289 1953 France 301 47 Appl. No.: 258,024

Related US. Application Data [62] Division ofSer. N0. 143,884, May 17,1971, Pat. No.

[52 us. 01 301/5 R [51] Int. Cl B60b 19/00 [58] Field of Search 301/5 R,46, 47,

[56] References Cited UNITED STATES PATENTS 2,228,423 1/1941 Ticktin 30147 3,226,128 12 1965 Grier 301/47 Primary ExaminerRichard J. JohnsonAssistant ExaminerReinhard J. Eisenzopf AttorneyAlvin E. Hendricson eta].

ABSTRACT Power operated legs pivot curved feed radially outward of awheel for fixing the rotary wheel position as upon uneven terrain or inthe presence of exterior forces tending to rotate the wheel. Whenretracted the feet circumferentially fit the wheel for ready rolling ofthe wheel to another location.

4 Claims, 8 Drawing Figures PAIENIEDnnvzo 1975 SHEET 10? 2 SELF-ALIGNINGWHEEL STRUCTURE This application is a divisional application of mycopending U.S. Pat. application Ser. No. 143,884 filed in the US. Pat.Office on May 17, 1971 for Sprinkler System Wheel Structure and now U.S.Pat. No. 3,684,180.

BACKGROUND OF INVENTION Many types of agricultural crops requireirrigation and overhead irrigation is normally provided by some type oflarge sprinkling system. In this respect there has been developed whatis termed a wheel roll sprinkler system wherein a pipe or sections ofpipe coupled together form the axles of a number of large spaced wheels.By the provision of a central drive mechanism that turns the pipe orline, the wheels may be rolled from one sprinkling location to anotherin a field, for example. This type of sprinkler system materiallyreduces the amount of manual labor involved in moving a sprinkler line.

One of the problems involved in the use of wheel roll sprinkler systemsis the necessity of ensuring that the sprinkler heads are perpendicularto the ground to obtain maximum irrigation water coverage. Variouscircumstances afiect the wheel position when the line is moved such asirregularities in the ground surface, mud, wind and possibleentanglement of the system with crops or the like.

In order to overcome the above-noted problems or difficulties with wheelalignment or positioning, there have been devised various methodsintended to hold the line in position. In this respect so-called dragstakes may be connected to the line to drag along the ground as the lineis moved forward but which are driven into the ground by any attemptedreverse movement of the line. This approach is primarily useful in areaswherein strong prevailing winds occur that might otherwise roll theline. There have also been devised various types of legs that may befolded out of the wheel to hold the wheel in position. However, theseare operated by hand and consequently require manual labor to fold orunfold the legs and, furthermore, fail to provide initial alignment orpositioning of the wheel. More prosaic approaches are found in theprovision of wood blocks that may be tied to the wheel to keep it fromrolling or even the mounding of dirt around the wheel to maintain it inadjusted or relocated position. Each of the methods noted above requirean operator to physically walk to the wheel to be aligned.

The present invention provides an improved wheel structure particularlyadapted for use with wheel roll sprinkling systems. Although the wheelstructure hereof is not limited to this application it is hereindescribed in connection therewith and it is noted that, with respect tothis application, the present invention automatically aligns the wheelafter each movement of the system to thus align the portion of thesystem on the side of the central drive mechanism carried by such wheel.

SUMMARY OF INVENTION The present invention provides a pair of curvedfeet disposed on the exterior periphery of a sprinkler wheel andconforming to the curvature of the wheel. Actuating means such as ahydraulic ram or cylinder is mounted within the wheel with legsextending from the piston rod of the cylinder into pivotal engagementwith the two above-noted feet. These feet are themselves pivotallymounted on the periphery of the wheel in back-to-back relationship withthe mountings being separated about 45 of are on the wheel.Additionally, the feet have a substantial length as of the'order of 45of are on the periphery of the wheel so that, upon being moved orpivoted outwardly of the wheel, they provide a substantial contact areawith the earth for initially righting the wheel into an upright positionand maintaining the wheel in such alignment. The length and spacing ofthe feet may be varied to suit conditions.

The invention furthermore provides for automatic return of the feetthereof, as by the mounting of one or more springs within the wheel andengaging the legs.

Application of water pressure to the system through the central pipe orline applies hydraulic pressure to the ram or cylinder hereof through aconnection to the pipe so that the feet are forced outwardly to alignthe wheel in upright position and the feet are maintained in extendedposition as long as water pressure is main tained in the system. Upontermination of water pressure by cutting off the flow of water to theirrigation system, the return springs then draw the legs upwardly tofold the feet back against the periphery of the wheel and automaticallyretain the feet in such position for movement of the system.

DESCRIPTION OF FIGURES The present invention is illustrated as toparticular preferred embodiments thereof in the accompanying drawingswherein:

FIG. 1 is a perspective view of one wheel of a wheel roll sprinklersystem and incorporating the present invention;

FIG. 2 is a side elevational view of the wheel of the present inventionwith the feet retracted for movement of the system;

FIG. 3 is a side elevational view of the wheel of the present inventionwith the support feet extended;

FIG. 4 is a central sectional view taken in the plane 44 of FIG. 3illustrating the interior of the hydraulic ram of the present invention;

FIG. 5A is a sectional view taken in the plane 5A5A of FIG. 3illustrating one manner of connecting the levers or legs of the presentinvention to the support feet hereof;

FIG. 5B is a partial sectional view in plane 5B5B of FIG. 2 illustratingan alternative connection of the levers or legs of the present inventionto the pivotally mounted support feet;

FIG. 6 is a central sectional view through an alternative ram actuatingarrangement; and

FIG. 7 is a schematic illustration of a wheel roll irrigation system inaligned and misaligned condition.

' DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings,there will be seen t be illustrated in FIG. 1 a wheel 11 for a wheelroll sprinkler system with a pipeline 12 of the system forming the axleof the wheel. Spokes l3 connect the axle and wheel rim 14. In practicethe wheel may have a substantial size such as, for example, 4 to 5 feetin diameter, and also has a substantial width of rim to readilyaccommodate rolling of the wheel over uneven terrain.

The wheel rim 14 may be corrugated as indicated in FIG. 1 and to thisextent the wheel illustrated is quite conventional. In accordance withthe present invention the wheel 11 is modified to provide a pair ofsupport feet 21 and 22 pivotally mounted by means of hinges 23 and 24respectively on the periphery of the wheel rim, as indicated in FIG. 3,for example. The support feet 21 and 22 have the same or substantiallythe same curvature as the wheel rim and are adapted to fit on theexterior of the rim, as indicated in FIG. 2, so as to provide noimpediment to the rolling of the wheel during movement of the sprinklersystem. Further with regard to the aligning and positioning feet of thewheel, it is noted that the hinges 23 and 24 are spaced apart a distanceof about 45 of are on the periphery of the wheel. The feet 21 and 22have a substantial length so as to provide maximized stability to thesprinkler wheel when the feet are pivoted outwardly, as discussed below.Each of the feet may, for example, subtend an angle of approximately 45on the periphery of the wheel.

The aligning feet 21 and 22 are adapted to be automatically pivotedoutwardly and retracted by actuation means. Such means may be comprisedas an electric motor, for example, controlled by water pressure in thesystem. Preferably, and probably most simply, such actuating means maybe provided as a hydraulic cylinder or ram 31 shown to be mounted in thewheel between the rim l4 and pipe forming the axle 12. The ram 31, as itis hereinafter termed, may take a variety of different configurationsand one possible configuration is illustrated in FIG. 4 wherein a piston32 is shown to be mounted within a cylinder 33 with this cylinderincluding end caps bolted to the wheel rim 14. A piston rod 34 extendsfrom the piston 32 through the bottom end cap of the cylinder intoengagement with a mounting unit 36 described in more detail below.Channel bars or straps 37 connect the ram to the central pipe 12 formingthe axle of the wheel. A connection 38 is provided from this axle pipe12 to the top of the ram cylinder 33 and this connection may, forexample, take the form of a hose. In practice there may be provided acollar about the pipe for attachment of the straps and the hose.Application of water pressure to the line 12 will thus be seen to alsoapply this pressure through the connector 38 to the top of the ramcylinder so as to force the piston 32 downwardly in the cylinder.

A pair of rod-like legs 41 and 42 are connected between the mountingunit 36 on the bottom end of the piston rod and the aligning feet 21 and22. The legs 41 and 42 are pivotally connected to the mounting unit 36as, for example, by the provision of a forked end on the leg 42 and aknife end on leg 41, all pinned to the mounting unit, as generallyindicated in FIG. 4. Mounting unit 36 carries rollers 39 on each end ofthe mounting pin for engaging the channel straps 37 to absorb sideloading of the piston rod. The legs 41 and 42 may be provided as solidrods or pipes of substantial strength and, if desired, may be providedwith means for varying the lengths thereof as generally indicated at 43of FIG. A. Each of the legs are, as noted above, pivotally connected toone of the feet and in this respect reference is made to FIG. 5Aillustrating the rod 41 as extending through a slot 46 in the wheel rim14 and having a lower forked end fitting over a central upward extension47 on the foot and pinned thereto. The legs are connected to the feet atapproximately the centers of the feet as regards length thereof and areadapted to pivot the feet outwardly from the wheel rim when the ram isactuated to drive the piston rod thereof downwardly toward the wheelaxle.

Various alternative manners of connecting the legs and feet are possibleand in FIG. 5B there is illustrated an alternative arrangement wherein aleg 41A is formed with a U-shaped end 51 extending about the wheel rimon the lateral sides thereof. A shaft 52 engages opposite ends of theU-shaped leg termination 51 in pivotal relationship thereto and in turnis bolted to the exterior side of the foot 21. Whatever the type ofpivotal connection of leg to foot, it is herein provided that thestructure shall be capable of moving the legs outwardly of the wheel topivot the feet about the hinged connection thereof to the wheel rim.

In addition to the foregoing elements of the present invention, there isalso provided hereby means for automatically retracting the feet fromthe extended position illustrated in FIG. 3 upon termination ofapplication of water pressure to the sprinkling system carried by thewheel hereof. Such means are herein illustrated as comprising a pair oftension springs 61 and 62 cor. nected to the interior side of the wheelrim 14 on opposite sides of the ram 31 circumferentially of the rim andeach connected to one of the legs 41 and 42. These springs are normallyin tension when the feet 21 and 22 are retracted against the wheel rimand are further extended against the restoring force thereof when thelegs pressure then forces the ram piston 32 downwardly in 7 feet 21 and22 about the hinges 23 and 24 thereof respectively into the positionshown in FIG. 3. The feet are maintained in this extended aligningposition by water pressure in the ram but as soon as such pressure isreleased by removing the pressure applied to the sprinkling system, thesprings 61 and 62 immediately retract the legs by pulling them upwardlyfrom the wheel so as to draw the feet 21 and 22 back into peripheralcontact with the wheel rim. It will be appreciated that the legs 41 and42 must be pivotally mounted at both ends thereof or some alternativeprovision be made for accommodating the necessary change in anglebetween the legs and at least the aligning feet as the legs are movedinwardly and outwardly of the wheel.

It will be appreciated that the present invention provides an automaticaligning and positioning mean for wheels of a wheel roll sprinklersystem as is employed in agricultural irrigation. Testing of the presentinvention has established that the aligning means hereof are capable ofrighting a sprinkler wheel having an initial inclination in excess of 67from desired position. As noted above, a variety of factors tend toinfluence the rotary position of the sprinkler wheel following movementof the system. In order for the sprinkler heads to properly operate theyare to be located in an upright for such positioning or alignmententirely automatically so that it is not necessary for an operator tophysically re-orient individual wheels and'block them in desiredposition. Inasmuch as a wheel roll sprinkler system has a substantialphysical area of structure, it is also possible for wind loads to movethe wheel and the present invention prevents any such movement so thatonce the system is moved and aligned or positioned by the presentinvention, such alignment or position is maintained as long as waterpressure is applied to the system. Release of water pressure results inautomatic retraction of the aligning feet of the present invention sothat the entire system is then ready for movement to a new location.Only the application and termination of water pressure is required forcomplete operation of the present invention.

As noted above, the present invention admits of various modifications.Additionally the invention is advantageously embodied to be adaptablefor mounting upon different wheels as, for example, in a wheel rollirrigation system; Preferably such mounting may be accomplishediwithoutthe necessity of extensive modification of the-wheel itself. Withrespect to certain variations of the presentinvention, reference is madeto FIG. 6 illustrating' an alternative hydraulic ram arrangement forpivoting the aligning feet between the extended and retracted':positions thereof. As shown, a ram 71 is providjed as a cylinder 72depending from a cylinder head 73*withiaasupport-and supply tube 74extending axially thmugh'the cylinder into connection with the cylinderclamp about the axle with the tube bein'g threaded into the clamp. Itisnoted, however, that the tube 74 extendsiinto communication-with theinterior of the pipe axle and also that the wheat its upper endcommunicates through openings in the cylinder head with thecylinderabove the piston 76. There is thus provided a fluid flow pathfrom the pipe 12 to theram 7 1'.

The, legs 41 and 42 are pivotally connected at the upperen ds thereof toa yoke 79 rigidly affixed to the piston.rod",77 adjacent the lower end'thereof. In FIG. 6 the yoke 79 is rotated 90 from actual position inorder to show the yoke. It will be seen that application of.waterpressure to the system, including the pipe 12, will applywaterpressure to the ram above the piston 76 thereof to force thepistondownwardly. This then slides thepiston rod 77 down about thesupport and supplytube 74 to move the yoke 79 toward'the axle and thustopivot'the aligning feet outwardly into the position illustrated in FIG.3. Provision is also made for automatically'returning the feet toretracted position and in this embodiment there is illustrated a coilspring 8 I disposed'about the support tube 74 in compression between theyoke 79 and axle 12. Thus the springwill be. seen to'continuously urgethe yoke radially outward oftheaxle and consequently termination ofwater pressurelapplied to the system allows the spring to forcethe yoke,and piston upwardly to retract the feet. The

strength of the spring 81'. is less than the force applied by the ram 71withv the piston thereof under pressure from the water system but. thespringis sufficiently strong to force thep'iston' upwardly when'waterpressure is released frorn' above-the piston.-

Although the present invention is not limited to-utilization with wheelroll irrigation systems, it is'particularly advantageous in connectionthereof. In this respect attention is invited to FIG. 7 of the drawingsschematically illustrating such a system and including the presentinvention. In FIG. 7A an irrigation system of the above-noted type isshown in aligned position, i.e., the pipe 91 extending through aplurality of wheels 92 is disposed in a straight line. At the center ofthe system there is provided drive means 93 for moving the system fromone location to another as, for example, progressively across a fieldbetween separate irrigating locations. As the system is moved from onelocation to another by the drive means 93 the nature of the terrain orthe like may impede the progress of certain wheels so that the system issomewhat out of alignment after movement. A mislined system isillustrated at FIG. 7B. With the present invention being provided on onewheel on each side of the drive means, as indicated at 94, applicationof water pressure to the line 91 will cause these wheels 94 to rightthemselves, i.e., to be rolled into desired'orient'ation so that thepipe will be tumedto dispose sprinkler heads 96 thereon upwardly. Thedrive means 93 is conventional and operates to rotate the pipe so thatthe wheels secured thereto roll during movement of the system. Themisalignment illustrated in FIG. 7B is exaggerated to emphasize theproblem overcome by the present invention.

Ina typical installation the individual wheels 92 may be separated adistance'of approximately 40 feet along the line and yet it is onlynecessary to provide one wheel in accordance with the present inventionon each side of the central drive means. Preferably these wheels 94' arelocated'well outwardly from the center of the system as illustrated. Itis not necessary to modify each of the wheels ofthe system in accordancewith the present invention in order to realize automatically alignmentof the system by the present invention.

Although the present invention has been described and illustrated withrespect to particular preferred embodiments thereof, it is not intendedto limit the invention to details of description or illustration.Various modifications and variations of the present invention will beapparent to those skilled in the art.

'What is claimed is:

l. A self-aligning wheel comprising a pair .of curved feet fitting theexterior of a wheel rim,

means pivotally mounting said feet on the rim at ends of the feetadjacent each other, and

actuating means secured to the wheel within the rim thereof andextending into engagement with said feet for pivoting said feetoutwardly of the rim and retracting the feet against the rim.

2. The wheel of claim lfurther defined by said actuating meanscomprising at least 'one hydraulic cylinder having a piston rodcontrollably extensible to pivot said feet radially outward of the wheelrim.

3.. A self-aligning wheel comprising a pair of curved feet fitting theexterior of a wheel rim,

ing said feet outwardly of the rim and retracting the feet againstthe;,rim.

4. The wheel of claim 1 furtherdefi nedjthe curva ture of said feetmatching the curvature of said wheel 5 rim whereby said wheel rollsfreely in retracted. position of said feet.

1. A self-aligning wheel comprising a pair of curved feet fitting theexterior of a wheel rim, means pivotally mounting said feet on the rimat ends of the feet adjacent each other, and actuating means secured tothe wheel within the rim thereof and extending into engagement with saidfeet for pivoting said feet outwardly of the rim and retracting the feetagainst the rim.
 2. The wheel of claim 1 further defined by saidactuating means comprising at least one hydraulic cylinder having apiston rod controllably extensible to pivot said feet radially outwardof the wheel rim.
 3. A self-aligning wheel comprising a pair of curvedfeet fitting the exterior of a wheel rim, means pivotally mounting saidfeet on the rim at ends of the feet adjacent each other, and actuatingmeans including a rod controllably movable radially inward of the wheeland a pair of rigid legs pivotally connected to said rod and pivotallyconnected one to each of said feet in spaced relation to the pivotalmounting of said feet for pivoting said feet outwardly of the rim andretracting the feet against the rim.
 4. The wheel of claim 1 furtherdefined by the curvature of said feet matching the curvature of saidwheel rim whereby said wheel rolls freely in retracted position of saidfeet.